Memory devices, such as flash memory devices (e.g., NAND, NOR, etc.), have developed into a popular source of non-volatile memory for a wide range of electronic applications. Non-volatile memory is memory that can retain its data values for some extended period without the application of power. Changes in threshold voltage of the cells, through programming (which is sometimes referred to as writing) of charge-storage structures (e.g., floating gates or charge traps) or other physical phenomena (e.g., phase change or polarization), determine the data value of each cell. Common uses for flash memory and other non-volatile memory include personal computers, personal digital assistants (PDAs), digital cameras, digital media players, digital recorders, games, appliances, vehicles, wireless devices, mobile telephones, and removable memory modules, and the uses for non-volatile memory continue to expand.
In some examples, memory devices might latch data for output, such as during a read operation, e.g., to a host. For example, the read data might be latched to input/output (I/O) circuitry of the memory device for output. In some examples, the read data might be latched to a read buffer, such as a read FIFO buffer, of the input/output (I/O) circuitry, e.g., that might be adjacent to output pins of the memory device.
Memory devices might include a data cache, for example, that may be connected between the read FIFO and an array of memory cells of the memory device. The data cache, for example, may temporarily store the data read from the array while the array is busy. The data may be passed from the data cache to the read FIFO and latched to the read FIFO for output.
For example, the data may be passed from the data cache to the read FIFO in response to a first clock signal and latched in the read FIFO in response to a second clock signal. However, differences in the structure of the paths for the data and the second clock signal, as well as process variations, may lead to timing difficulties in latching the data to the read FIFO while the data is valid.